Phenotypic and functional analyses of peripheral blood T cells in women with recurrent spontaneous abortion in early stages of pregnancy

1 Department of Obstetrics and Gynecology University of Turin Turin, Italy2 Hematological Division Department of Experimental Medicine and Oncology University of Turin Turin, Italy

Aim. The aim of this study was to investigate the subset distribution and proliferative response of peripheral blood (PB) T cells in a group of pregnant women who experienced previous unexplained recurrent spontaneous abortion (RSA) in comparison with a control group of healthy pregnant women.Methods. Twenty women with RSA and 25 fertile women in the 1st trimester of pregnancy were included in the study. Activation antigens of peripheral T lymphocytes and their proliferative response were compared. The PB lymphocytes were stained with monoclonal antibodies. The in vitro T cells proliferation analyses were performed by stimulation with anti-CD3, interleukin-2 and phytohemagglutinin.Results. Percentage and absolute number of T CD4+ lymphocytes were significantly higher in patients with RSA than in fertile pregnant women. Analysis of CD4+ T cells subpopulation showed that RSA patients displayed a lower proportion of CD25+ cells and a lower expression of H4/ICOS activation antigen. T cells from patients with RSA display a decreased proliferative response to all the stimuli used.Conclusion. These data underline that an altered modulation of maternal CD4+ T cell population is associated with unexplained recurrent abortion.